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arXiv · 2304.05113

Centrosymmetric-noncentrosymmetric Structural Phase Transition in Quasi one-dimensional compound, (TaSe$_4$)$_3$I

Arnab Bera·Samir Rom·Suman Kalyan Pradhan·Satyabrata Bera·Sk Kalimuddin·Tanusri Saha-Dasgupta·Mintu Mondal
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Abstract

(TaSe$_4$)$_3$I, a compound belonging to the family of quasi-one-dimensional transition-metal tetrachalcogenides, has drawn significant attention due to a recent report on possible coexistence of two antagonistic phenomena, superconductivity and magnetism below 2.5~K (Bera et. al, arXiv:2111.14525). Here, we report a structural phase transition of the trimerized phase at temperature, $T~\simeq$~145~K using Raman scattering, specific heat, and electrical transport measurements. The temperature-dependent single-crystal X-ray diffraction experiments establish the phase transition from a high-temperature centrosymmetric to a low-temperature non-centrosymmetric structure, belonging to the same tetragonal crystal family. The first-principle calculation finds the aforementioned inversion symmetry-breaking structural transition to be driven by the hybridization energy gain due to the off-centric movement of the Ta atoms, which wins over the elastic energy loss.

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Arnab Bera, Samir Rom, Suman Kalyan Pradhan, Satyabrata Bera, Sk Kalimuddin, Tanusri Saha-Dasgupta, Mintu Mondal. 2023-04-11. Centrosymmetric-noncentrosymmetric Structural Phase Transition in Quasi one-dimensional compound, (TaSe$_4$)$_3$I. https://doi.org/10.1103/physrevb.108.035112

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